UNCLASSIFIED Lieutenant Commander James T. Westwood, USN

Electronic Warfare and

at the Outset of

The role and importance of and The broad strategical consequences of this single signals intelligence in modern wars of the last one­ naval tactical electronic warfare action were far­ hund red years-and more-is a fascinating one. Some­ reaching, materially contributing to the eventual Al­ times, we forget some of the critical differences which lied victory: the German cables ran to Brest, France; EW and Sigint have made in modern warfare. These Vigo, Spain; Tenerife, Canary Islands; and to New differences sometimes have had little to do with the York City. From those points, by various routes and tactical or strategic intelligence value of enemy com­ relays, communications could have been effected with munications; rather, they have pertained to the fact German interests, allies, agents, and friends in the or act of electrical communications themselves. On Americas, Africa, and the Near East. Since German occasion, the distinctions between "tactical" and cables in the Mediterranean Sea were British-owned, "strategic" are blurred as tactical operations give rise the only cable left to German use was one running to results of strategic proportions. from West Africa to Brazil. In fact, one such event constituted Great Britain's Bulloch appraises the Sigint payoff of this essentially first offensive action of World War I. According to EW operation like this: "This meant that all urgent John Bulloch, in 1912 the British Committee of German messages, diplomatic, naval, and military, Imperial Defence decided that, should war break out had to be sent by the powerful radio station of Naven, with Germany, one of the initial British operations outside . In those days, wireless was nowhere as must be to forestall the use of German international advanced as it is now, but it was realized that (radio) underwater cables. 1 A secret "war reserve" standing broadcasts could be intercepted, and German code order was issued to this effect, to be implemented messages began to pour into the Admiralty."' posthaste once war was declared. The successes of British cryptanalysts in the Ad­ On 5 August 1914, His Majesty's cable ship, Tel­ miralty's under Admiral William Reginald conia, quietly left her berth and steamed to a position Hall have become legendary. Room 40 was staffed by off Emden. Within a few hours, five German cables about 50 expert cryptanalysts, plus support personnel, running under the were grappled, working around-the-clock shift schedules. They pro­ lifted, and cut. A few days later, in the interest of duced daily summaries, spot reports, and special thoroughness, Telconia returned to the scene, picked reports based on raw collection provided by intercept up the cables and reeled aboard several thousand and DF stations located in the British Isles at such feet-just to make sure the Germans would not be places as Lowestoft, York, Murcar, and Lerwick. able to repair the damage. Recoveries of cipher and code books from derelict or battle-damaged German , submarines, and ' John Bulloch, M.l.5: The Origin and History of the British Counter- Service (London: Arthur Baker, Ltd., 1962), pp. 144-145. ' Ibid, p. 145,

24 UNCLASSIFIED UNCLASSIFIED surface ships greatly aided the cryptanalytical effort planned, two years in advance, to occur at the outset in Room 40, a process dubbed "practical cryptanaly­ of war. sis." After the war, it was estimated that Room 40 • This C3CM operation was a mere act of physical had solved some 15,000 German naval and diplomatic disruption, rather than "hard kill," , cover, communications, a very great number considering that or electrical disruption-all of which would have been recoveries were hand-generated. Among Room 40's more difficult and costly to execute - i.e., cost­ preeminent achievements were its contribution to the effectiveness does not necessarily mean limited results. British victory in the Battle of the Dogger Bank and • The agent provocateur was an innocuous, inglo­ the decipherment of the infamous Zimmermann rious, noncombatant cable ship, not a warship - i.e., Telegram. beware of the rear services. • Whether or not the original planners anticipated Aside from the professional interest of this account, the vast Sigint results of their operation, this is one some contemporary significance and morals can be case in which the decision to disrupt enemy commu­ drawn. Among them: nications turned out to be far more propitious than • In today's terms, the Committee of Imperial would have been a decision to remain passive, subse­ Defence's strategy (giving rise to the cable ship's quently to exploit those communications. It made "naval offensive") equated to a counter-command con­ exploitation of a wholly new kind possible, laying a 3 4 trol communications (C CM or C ) operation on a foundation for many years of successful Sigint grand or geopolitical scale - i.e., strategic C3CM was operations.

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